转 文件路径相关的字符串操作

uses
HTTPApp, Masks;

procedure TForm1.Button1Click(Sender: TObject);
var
ss,s: string;
begin
//先提取一个文件名的字符串
ss := Application.ExeName;
ShowMessage(ss); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects\Project1.exe

//路径
s := ExtractFilePath(ss);
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects\

//所在文件夹
s := ExtractFileDir(ss);
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects

//所在逻辑盘
s := ExtractFileDrive(ss);
ShowMessage(s); //C:

//文件名
s := ExtractFileName(ss);
ShowMessage(s); //Project1.exe

//文件扩展名
s := ExtractFileExt(ss);
ShowMessage(s); //.exe

//相对路径
s := ExtractRelativePath('C:\Documents and Settings\wy\My Documents\',ss);
ShowMessage(s); //RAD Studio\Projects\Project1.exe

//dos下的短文件名
s := ExtractShortPathName(ss);
ShowMessage(s); //C:\DOCUME~1\wy\MYDOCU~1\RADSTU~1\Projects\Project1.exe

//转换到Unix路径格式, 需要 uses HTTPApp
s := DosPathToUnixPath(ss);
ShowMessage(s); //C:/Documents and Settings/wy/My Documents/RAD Studio/Projects/Project1.exe

//转Unix路径格式为Window格式, 是 DosPathToUnixPath 的逆操作
s := ExpandUNCFileName(DosPathToUnixPath(ss));
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects\Project1.exe

//去掉结尾的路径分隔符
s := ExcludeTrailingPathDelimiter(ExtractFilePath(ss));
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects

//去掉结尾的路径分隔符, 只是调用:ExcludeTrailingPathDelimiter
s := ExcludeTrailingBackslash(ExtractFilePath(ss));
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects

//更换扩展名, 并不修改文件, 只是替换字符串:
s := ChangeFileExt(ss,'.bak');
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects\Project1.bak

//更换文件路径:
s := ChangeFilePath(ss,'c:\temp');
ShowMessage(s); //c:\temp\Project1.exe

//判断第几个字符是否是路径分隔符:
IsPathDelimiter(ss,3); //返回 True

//判断后缀名是不是 exe; 需要 uses Masks
MatchesMask(ss,'*.exe'); //返回 True
end;

//分解 ProcessPath (需要 uses FileCtrl)
var
s,p,f: string;
d: Char;
begin
s := ParamStr(0);
ShowMessage(s); //C:\Documents and Settings\wy\My Documents\RAD Studio\Projects\Project1.exe
ProcessPath(s,d,p,f);
ShowMessage(d); //C
ShowMessage(p); //\Documents and Settings\wy\My Documents\RAD Studio\Projects
ShowMessage(f); //Project1.exe
end;

//压缩显示 MinimizeName (需要 uses FileCtrl)
var
s: string;
begin
s := ParamStr(0);
s := MinimizeName(s,Self.Canvas,100);
ShowMessage(s); //C:\...\Project1.exe
end;